hi all dear members…
this summer i have a final year project to graduate as an electrical engineer …
my topic is to design and implement a simulator of a protective grounding system that contains the 3 types of circuits … that it :
TT, IT, and TNC(s) … and adding the adequate protective circuit and so on ….
i found some data but still not enough … would be glad if you help me here ….
pease pleaaaaaaaaaaase help me ////
thnks in advance ..
Hawk .

 

What exactly are you looking for? Specific questions/problems?
Surely you don't expect someone to write down EVERYTHING about that topic do you?

http://www.electrical-installation.org/enwiki/Characteristics_of_TT,_TN_and_IT_systems

 

my purpose is to implement a simulator ( circuit) that describes how the 3 types of grounding are working ...
for educational purpose .. that is i will let this circuit in my isntitut as a good example of grounding

the steps are ...
i need power supply ..
a load ( resistors) ...
and i need protective elements ...
and each type of grounding as a specific adequate protective element ....
example :
the TT grounding type needs the differential relay ...
the IT needs impedance controller and so on .....

so i need those details ..
i want to simulate them in simulink (matlab) before implementing the circuit ....

hope it is clear ...
please help me soon ....
time is running ...

 

Will you cut your diploma in half and send it to us for the help?

 

!!!!!
is that a joke or what ?
even great scientists need help !
anyway ... thnks

 

Don't worry. Everybody needs help sometimes. Anyway, if you can be as clear as possible about what you're asking, we may be able to help more. It sounds like you would like to simulate simple circuits utilizing various types of grounding schemes. Am I correct?

Are you asking for help choosing a simulation tool? Or are you looking for information on these grounding schemes? Or both? Perhaps I'm missing your point all together.

I don't know much about grounding schemes, unfortunately, but I have done a healthy amount of circuit simulation. LTSpice is popular and free. OrCad is also popular but quite expensive. I have never simulated circuits in MatLab, but I'm sure somebody here will be able to help with that. There are, literally, hundreds of SPICE implementations and a little googling goes a long way.

 

hi aws505
as u said ... i woud like to simulate simple circuits utilizing various types of grounding schemes ( TT,IT,TNS(C)) .....
as you said ... i think using matlab is not a good idea .... i think a software like MULTISIM .... pspice is so old i think and i hated it since the days of lab sessions hehe ...
my 1st question is : what should the circuit look like ... of course i want simple one ..
power supply + transformer + load ( resistors generally) and so on ...
my second question which is the most important one is :
how can i do the tests on the grounding performance ? i am really lost here ..

hope it is a bit clear now ....
if now ... i am happy to see your questions ....

 

Well... I think that the link mcgyvr should be very helpful for determining what you need to include in such a circuit. It looks like you will need to model grounding schemes in your simulation: This means that you will likely have to guess (or research) the unwanted performance that may arise from these various grounding schemes. I would suggest looking into "parasitic inductance" and "parasitic capacitance." Also, try doing some real calculations for the resistance of the wires that would lead to an earthing electrode and include these resistances in your simulations.

Testing the "grounding performance" of a particular grounding scheme doesn't seem very straight-forward. What exactly does your instructor want you to show? Are you simply supposed to produce schematics for these schemes, or are you actually supposed to test them? How are you to test them? Perhaps you should ask your instructor a few more questions...

 

here is the update ...
yesterday i talked to my instructor .. he said the simulation using software is not necessary .... now i have to implement the circuit only ...
and as you said.. i need to create the "unwanted performance" that is the faults ...
for example the short circuit and the overloading and so on ...
i also i invastigate what protective element is suitable for each grounding type ....
for example the short ciruit relay will not operates in the TT type .. but we need differential relay .... and so on with the other types ....

till now i need a case and power source .. power transformer to isolate the circuit .. and some elements ....
if i find a problem i will post it here .... so please time by time take a look at this thread ....
thnks a looooooot aws505 ....